Inhibition of breast cancer cell proliferation by low-intensity pulsed ultrasound (LIPUS).

Cancer is the second leading cause of death in the United States, preceded only by heart disease. Cancer cells display an uncontrolled proliferation, controlling which has been a big challenge for cancer treatment. Ultrasound is best known for its application in diagnostic imaging; it is also a vehicle for delivering high frequency mechanical stimulation toward beneficial bio-effects. Unlike high intensity focused ultrasound, which is recently being investigated for thermal ablation of solid tumors, low intensity pulsed ultrasound (LIPUS) is directed toward cellular mechanisms. The effects of LIPUS on cancer cell proliferation are not known. Here, we demonstrate that LIPUS dose-dependently inhibits proliferation of breast cancer cell T47D as determined by several biochemical assays such as MTS, Alamar Blue, and BrdU assay. Statistically significant inhibition of T47D cell proliferation is observed when cells are exposed to 50-100 mW/cm(2). For this intensity range, LIPUS excitation inhibits the proliferation of T47D cells upto 50%. We also notice that inhibition of cell proliferation by LIPUS depends on its exposure time on cells. Minimum exposure time of LIPUS excitation for pronounced inhibitory effects on T47D cell proliferation is approximately 10 min.

PMID: 21974304